Pat Mayse Lake: 94.5% full as of 2026-09-05

Historical Data

Date Percent Full Mean Water Level
(ft) 		Reservoir Storage
(acre-ft) 		Conservation Storage
(acre-ft) 		Conservation Capacity
(acre-ft) 		Surface Area
(acres)
Most recent 2026-09-05 94.5 449.88 111,597 107,437 113,683 5,518
1 day prior 2026-09-04 94.7 449.91 111,762 107,602 113,683 5,521
2 days prior 2026-09-03 94.8 449.95 111,983 107,823 113,683 5,525
1 week prior 2026-08-29 95.6 450.11 112,869 108,709 113,683 5,542
1 month prior 2026-08-05 99.6 450.92 117,393 113,233 113,683 5,629
3 months prior 2026-06-05 94.6 449.90 111,707 107,547 113,683 5,520
6 months prior 2026-03-05 88.6 448.64 104,905 100,745 113,683 5,284
1 year prior 2025-09-05 97.7 450.54 115,262 111,102 113,683 5,588
*

Percent Full is based on Conservation Storage and Conservation Capacity and doesn't account for storage in flood pool.

**

   Values above, including today's are averaged conditions. For near real-time instantaneous water level, see table below or the interactive map viewer.

Most Recent Instantaneous Water Level

Date/time Water Level
(ft) 		Conservation Pool Elevation
(ft) 		Height Above Conservation Pool
(ft)
Most recent 2026-09-05 23:00 449.86 451.00 -1.14 below flood pool
1 hour prior 2026-09-05 22:00 449.86 451.00 -1.14 below flood pool
2 hours prior 2026-09-05 21:00 449.86 451.00 -1.14 below flood pool
6 hours prior 2026-09-05 17:00 449.86 451.00 -1.14 below flood pool
12 hours prior 2026-09-05 11:00 449.88 451.00 -1.12 below flood pool
24 hours prior 2026-09-04 23:00 449.89 451.00 -1.11 below flood pool
48 hours prior 2026-09-03 23:00 449.92 451.00 -1.08 below flood pool
*

Data is provisional and subject to revision.

Additional Information

Impoundment date 1967-01-01
Vertical datum NGVD29
Dead pool elevation 415.00 ft above NGVD29
Service spillway crest elevation 451.00 ft above NGVD29
Emergency spillway crest elevation 477.00 ft above NGVD29
Flood pool elevation 460.50 ft above NGVD29
Top of dam elevation 488.50 ft above NGVD29
Conservation pool elevation 451.00 ft above NGVD29
Data download (CSV) period of record, last one year, last 30 days

Elevation-Area-Capacity Curves

1967-01-01 (source: USGS)
2008-07-01 (source: TWDB) : GIS Data
Data Source USACE:MYST2

Lake Location